OBJECTIVES: To examine changes in survival rates among low-birth-weight (LBW) infants between the years 1950 and 1996.METHODS: Survival figures were analysed for LBW infants managed at Baragwanath Hospital, a tertiary care centre in Soweto, Johannesburg, over four periods spanning five decades.RESULTS: The overall mortality rates of LBW infants decreased markedly between the early 1950s and the period 1995/96. By the mid-1990's approximately four times the number of infants with birth weight less than 1,500 g were surviving compared with the early 1950s. The reduction in mortality rates occurred in all LBW groups during the first three decades. However, since 1981 infants who weighed less than 1,500 g at birth were the major contributors to the overall reduction in mortality. Between the years 1981/82 and 1995/96, survival increased significantly from 64% to 79% for infants with birth weight 1,000-1,499 g, and from 14% to 32% for those with birth weight less than 1,000 g. Since infants in the latter group were seldom offered mechanical ventilation or artificial surfactant, a large part of these increases in survival can be attributed to improvement in the general level of care.CONCLUSION: There have been dramatic improvements in the survival of LBW infants over this time period at Baragwanath Hospital. Although newer interventions such as mechanical ventilation and artificial surfactant have played a significant role, improvement in care at primary and secondary levels has been of major importance.